Various proposals have been made to permit a train of vehicles to be driven a long distance over railroad tracks on their own railroad wheels; the train split up; and then picked up, individually, by highway tractors and distributed to various places near the freight yard.
In many of these the vehicle has both railroad and highway wheels and mechanisms for selectively substituting one for the other. This involves carrying heavy railroad equipment, particularly in wheels and axles, along the highway which greatly reduces the permissible payload. The present inventor has proposed removing the one type of wheels and substituting the other type and having a removable dolly at the front end for railroad service.